This invention relates generally to a fluid control valve and, more particularly, to an electromagnetically operated fluid control valve.
Electromagnetic actuators are commonly utilized for operating fluid control valves. Such an actuator is typically mounted within the valve housing and is often in direct fluid flow communication with the interior thereof so that it is subjected to contamination and corrosion caused by some fluids, such as steam, passing through the valve.
Another problem encountered with electromagnetically operated fluid control valves is that when the armature of the magnetic control assembly is utilized as a flapper valve element for closing a port, the valve suffers non-linearity. That is, the rate of flow of fluid through the valve is not proportional to the input signal to the magnetic control device. Hysteresis is also a problem and results from mechanical energy being degraded to heat energy and is indicated by the failure of the armature to return to its original position when the input signal is reduced to a previous value. Such problems ococur, for example, when the armature is pivotally connected to the valve housing by sheet metal strips.
The purpose of the present invention is to minimize the foregoing problems in prior art electromagnetically operated fluid control valves.